Gail Carriger has been advised that Eastercon might not be the best venue for her/her work. Not in any absolute-don't-go sort of way; indeed, she said she would follow up by dropping programming a line since she'll be in London around then anyways. I should note I really do have no more information than this: no idea of who or why she was advised against Eastercon and, frankly, not even really enough knowledge of her market to be certain one way or the other if they are right.
And yet - Eastercon has so many synergies with her work, especially in recent years. Well-attended steampunk balls. Victorianesque combat demonstrations. A strong support for both fantasy and science fiction and the grey scales in between. The recent Sherlock Holmes revivals should, if anything, accentuate interest in these things.
Now, it's true there's never much representation from the romance end of the these subgenres at the convention - at most, a token panel or so in a given year; but that's only one aspect of her work.
It's not as if I really know much about marketing; or, indeed, much about this particular situation or this particular year's worth of Eastercon programming, and there are (usually) always more attendees and authors and editors and artists etc. with ideas for the committee. But at least some of you (taldragon, for one) will be interested that she'll be in London in early April and may (or may not) be doing some public events as part of that trip.